JRM Vol.34 No.2 pp. 382-389
doi: 10.20965/jrm.2022.p0382


Development of Flexible Electro-Hydraulic Spherical Actuator

Wataru Kobayashi*, Hiroaki Tamaki**, Tetsuya Akagi*, Shujiro Dohta*, and So Shimooka***

*Okayama University of Science
1-1 Ridai-cho, Kita-ku, Okayama 700-0005, Japan

**SMC Corporation
4-2-2 Kinunodai, Tsukubamirai-shi, Ibaraki 300-2436, Japan

***Okayama University
2-1-1 Tsushima-naka, Kita-ku, Okayama 700-8530, Japan

September 17, 2021
January 6, 2022
April 20, 2022
flexible electro-hydraulic cylinder, flexible electro-hydraulic spherical actuator, gear pump with encoder, sequential control
Development of Flexible Electro-Hydraulic Spherical Actuator

Flexible electro-hydraulic spherical actuator

Voluntary rehabilitation at home helps to prevent the joint contracture after medical treatment. Our previous studies concerned a low-cost portable rehabilitation device using a flexible spherical pneumatic actuator as a passive exercise device. However, the device requires a bulky compressor to drive it. This study results in a compact fluidic driving system that is highly flexible. The system adopts a flexible electro-hydraulic cylinder driven by an electric motor and a hydraulic gear pump. An empirical equation for the suitable pump rotation for the desired displacement of the system has been determined. As a result, the multi-position control of the system within the tracking error of 4 mm has been realized by using the on/off control scheme based on the obtained equation. In addition, a flexible, spherical electro-hydraulic actuator using two proposed drive systems is developed and tested. Control of the attitude of the tested spherical actuator is successfully realized.

Cite this article as:
Wataru Kobayashi, Hiroaki Tamaki, Tetsuya Akagi, Shujiro Dohta, and So Shimooka, “Development of Flexible Electro-Hydraulic Spherical Actuator,” J. Robot. Mechatron., Vol.34, No.2, pp. 382-389, 2022.
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Last updated on May. 20, 2022